1. Field of the Invention
The present invention is generally related to a starting system for a marine engine and, more particularly, to a starting system that provides a fast and reliable initiation of the engine operation without requiring the operator of a marine vessel to manipulate a throttle handle prior to activating the ignition system.
2. Description of the Prior Art
Many different types of systems have been developed to assist in starting an internal combustion engine, particularly when the engine is cold.
U.S. Pat. No. 3,888,223, which issued to Mondt on Jun. 10, 1975, describes a carburetor enrichment system. An air fuel supply system for an internal combustion engine has a carburetor connected to the intake manifold of the engine with a plurality of large diameter vapor ports formed below the carburetor throttle. A vapor pump draws hydrocarbon vapors and air from the gas tank and from a fuel vapor evaporative control canister having a vent opening thereto and an inlet connected to a vent conduit from the top of the gas tank.
U.S. Pat. No. 3,924,591, which issued to Bond et al. on Dec. 9, 1975, describes a quick warm-up intake manifold. The temperature control system for an intake manifold stove to vaporize fuel droplets during a cold enrichment mode of carburetor operation is disclosed. The system includes a heat riser valve operated in accordance with engine coolant temperature by means of a thermal vacuum valve operatively connected to a vacuum operator coupled to the heat riser valve.
U.S. Pat. No. 3,977,380, which issued to Atsumi et al. on Aug. 31, 1976, describes a starter assist device for an internal combustion engine. A starter assist device includes a supplemental air supply passage for the intake manifold arranged to bypass the carburetor, and a thermo-sensitive switch incorporated in the starter circuit and arranged to cause introduction of supplemental air into the intake manifold when the engine is started under conditions in which the engine is warm so that an oversupply of fuel is avoided, and to close off the supplemental air when the engine is started when cold to provide an adequate amount of fuel.
U.S. Pat. No. 4,461,249, which issued to Majkrzak on Jul. 24, 1984, describes a method and apparatus of starting a cold engine. The method includes heating intake air and a carburetor of a dead, cold internal combustion engine of a first vehicle which uses an apparatus that heats the cold engine with energy supplied by a second vehicle having a running internal combustion engine.
U.S. Pat. No. 4,481,914, which issued to Ishida on Nov. 13, 1984, describes an accelerator-pump system for carburetors. The pump supplies additional fuel into a primary intake passage when a primary throttle valve is opened. A vacuum-operated actuator is responsive to a vacuum developed in a manifold passage upon cranking for actuating an accelerator pump plunger to discharge extra fuel into the primary intake passage.
U.S. Pat. No. 4,495,904, which issued to Sakaino et al. on Jan. 29, 1985, describes an apparatus for facilitating engine starting. A solenoid operated cut valve controls flow through a vent passage leading from a float chamber for a carburetor for an internal combustion engine. A normally closed switch opens in response to high temperature of the engine, and a normally closed timer switch opens at the start of cranking and closes again after a predetermined time of cranking.
U.S. Pat. No. 4,509,472, which issued to Slattery on Apr. 9, 1985, discloses a starting enrichment of alternate firing two cycle internal combustion engine. A two cycle internal combustion engine has at least two cylinders which fire alternately with pressure in one crankcase at the time when a vacuum is in the other. Supplemental fuel flow passages extend from each crankcase and are joined at a common passage connected to the float bowl of the carburetor.
U.S. Pat. No. 4,763,625, which issued to Staerzl et al. on Aug. 16, 1988, discloses a cold start fuel enrichment circuit. The circuit for an internal combustion engine includes a thermistor sensing engine temperature, a voltage source continually biasing the thermistor such that the voltage across the thermistor continually varies with engine temperature and provides an output fuel enrichment signal, and a circuit connecting the engine battery through the start switch to the thermistor to additionally bias the thermistor during cranking of the engine. A combination cold start and knock prevention fuel enrichment circuit is also provided.
U.S. Pat. No. 4,836,157, which issued to Miller on Jun. 6, 1989, describes a cold start engine priming and air purging system. A fuel delivery system for purging air from the reservoir of a diaphragm carburetor on an internal combustion engine and for supplying priming fuel to the carburetor air intake is described. A manual pump has an inlet coupled by a fuel line through the carburetor reservoir to a fuel supply, and an outlet connected by the fuel line to the constant flow rate nozzle orifice positioned at the carburetor air intake.
U.S. Pat. No. 4,905,641, which issued to Miller on Mar. 6, 1990, describes a cold start engine priming and air purging system. The system for purging air from the reservoir of a diaphragm carburetor on an internal combustion engine is described. It supplies priming fuel to the carburetor air intake. A pump is responsive to electrical signals from priming control circuitry to draw fuel through the carburetor reservoir and to provide fuel under pressure to a nozzle positioned at the carburetor air intake.
U.S. Pat. No. 5,554,322, which issued to Kobayashi on Sep. 10, 1996, describes an apparatus for supplying starting fuel for a carburetor. The carburetor has a main fuel jet and a throttle valve in a mixing passage and an apparatus for automatically supplying an enriched fuel and air mixture when an engine is cranked for starting and initial running of the engine upon starting.
U.S. Pat. No. 5,934,260, which issued to Gadkaree et al. on Aug. 10, 1999, describes a fuel vaporization system for starting an internal combustion engine. A cold start fuel vapor emission control system is disclosed which has an intake manifold and a fuel tank. These comprise a housing for containing a honeycomb absorber for absorbing fuel vapor, a vapor passage for fluidly connecting the housing and the fuel tank, a charging system for measuring the quantity of absorbed fuel vapor, and a purging passage connecting the housing to an intake manifold for introducing a mixture comprised of the fuel vapor and air to the intake manifold.
U.S. Pat. No. 6,375,526, which issued to Ikuma et al. on Apr. 23, 2002, describes an outboard engine system. The engine includes an engine block, a cylinder head coupled to the engine block and having an intake port in one side thereof, a carburetor including a carburetor body disposed on one side of the engine block adjacent the intake port and having an intake passageway, and a bypass-type starting device mounted to the carburetor body, and an intake pipe means which connects the intake passageway and the intake port to each other.
U.S. Pat. No. 6,779,503, which issued to Rado on Aug. 24, 2004, describes an automatic engine priming system for rotary mowers. The priming system for a carburetor for small internal combustion engines is described, wherein the priming system is remotely actuated and includes an automatic primer disabling feature operative when the engine is in a warm condition to prevent the supply of an overly rich fuel/air mixture to the engine intake system during warm restarts.
U.S. Pat. No. 6,799,545, which issued to Shaw on Oct. 5, 2004, describes a carburetor start pump circuit. The circuit is for starting an engine and has an auxiliary fuel pump mounted on a relatively standard carburetor body, a start pulse passage extending through the carburetor body to the auxiliary fuel pump, and a fuel circuit having an intake side which extends from a metering chamber of the carburetor body to the auxiliary fuel pump and a discharge side which is interconnected to the intake side and extends from the auxiliary fuel pump to a throttle bore in the air intake of the carburetor body.
The patents described above are hereby expressly incorporated by reference in the description of the present invention.
In marine propulsion systems known to those skilled in the art, it is typical that an initial engine starting procedure, when the engine is cold, begins with a manual movement of a throttle handle from a neutral position to a wide open throttle (WOT) position in order to activate the accelerator pump for the purpose of providing fuel to the carburetor. The control handle, or throttle handle, of the marine vessel, is then moved back to a quarter throttle position in order to leave the throttle plate open for the purpose of providing sufficient air flow during the starting process. This procedure is not always followed precisely and, as a result, the operator of the marine vessel sometimes experiences difficulty in starting the engine of the marine propulsion system.
It would be significantly beneficial if a fuel system could be provided in order to assure more reliable and faster starting of the engine without requiring the operator to first manipulate the throttle handle in the manner described above. This would permit the operator of the marine vessel to simply activate the ignition system to start the engine.